US1617225A - Drill sharpener - Google Patents

Drill sharpener Download PDF

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US1617225A
US1617225A US656985A US65698523A US1617225A US 1617225 A US1617225 A US 1617225A US 656985 A US656985 A US 656985A US 65698523 A US65698523 A US 65698523A US 1617225 A US1617225 A US 1617225A
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Prior art keywords
casing
valve
port
piston
cylinder
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US656985A
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Arthur H Skaer
Omar E Clark
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DENVER ROCK DRILL Manufacturing CO
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DENVER ROCK DRILL Manufacturing CO
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21KMAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
    • B21K5/00Making tools or tool parts, e.g. pliers
    • B21K5/02Making tools or tool parts, e.g. pliers drilling-tools or other for making or working on holes
    • B21K5/06Dressing, e.g. sharpening rock drills

Definitions

  • the present invention relates to rock drill sharpeners of the type in which clamping dies are employed for holding a drill steel, and associated therewith is a Huid operated dollying hammer, the objeetbeing toA provide a compact and effective mechanism in which the operation of the different members is controlled in proper sequence by novel valve mechanism.
  • Figure 1 is aside elevationof a Sharpener equipped with the novel mechanism
  • Figure2 is a front elevation of the, same with the front facing plate removed
  • Figure 3 is a corresponding rear elevation
  • Figure 4 is a vertical longitudinal :sectional View, -Y
  • v. Figures 5, 6 and 7 are verticalsectional views somewhat diagrammatic in their character, and illustrating the diiferent'positions of the controlling piston valve
  • Figurev 8 is a Vvertical. sectional view Vthrough the valve casing ⁇ illustrating its mounting on the cylinder, 4
  • Figures 9 and l0 are horizontal sectional views on. the lines 9- 9 andzlO-l-l() ofFig- Y ure 8,
  • Figure 11 is a detail sectional view of vthe valve operating handle crank and lock
  • Figure 12 is a detailview'of the quadrant rack or stop meansv for said handle crank.
  • Y v n In the embodiment illustrated an outer casing 13 ⁇ is employed, rhaving front [and rear openings 14- and 15 that'inay be closed by suitable detachable lplates or ywalls 16 and 17 shownin Figure 4.
  • the top of the casing constitutes a platform or table 18,
  • the die 19 is fixed onthe table top and the die; 2O moves down andp'up toward. and from the same. Itis 'carried byvertically reciprocating rods 22 spaced .apart and' connected at theirlower ends within the casing by a. cross head 23.y Thisy cross head has a central depending stem 24; slidably mountedA in a verticall bearing 25 formed in thelbase 26 of the casing. A lever 27fulcrumed'be.-
  • This pistonl hasa pitmanconnection 37 ,with
  • the cylinder 34' has a flattened portion 38 forming a base, to whichfis'bolted avertical tubular valve casing 39, fastening bolts being illustrated at 40.
  • the valve casingl is open endend, and saidopen .endsdesignated 41 Vand 42respectively constitute exhaust ports.
  • -Anf other internaly annular groove 48 located below theigroove44, has van outlet port 49 leading therefrom, and communicating bymeans of a passageway 50 with the interiorofthe cylinder 34 at its lower end below the piston 36.
  • the lower surface Lof said piston 36b constitutes a pressure surface-.that comprises the entire-area of the piston.
  • a fourth internal annular. groove 51 is .formed in the valve casing below Athe Agroove 48, land' an ou-tlet port 52, openingthererom, isconnected by a .hose 53 tothe vfluid operated hammer 21.
  • this ciprocaltory -piston valve comprising -a cenltral reduced bodyg54, having an upper head 55 anda lower ⁇ head156,-the heads fslidably fitting the interior of said casing.
  • the valve is supported by a vertical stem 57 that projects upwardly within the casing and is preferably surrounded by a coiled spring 58 operating to normally hold the valve in its uppermost position, or as illus trated in Figure 5.
  • rlhe stem is suitably connected to one arm 58 of a bell crank j ournaled within the casing, as shown at 59, and the other arm 60 of said bell crank has a link connection 61 with a crank arm 62 on a rock shaft 63 journaledin one side.v of the casing, and projectingtherefrom.- l
  • the projecting end' carries an upstanding handle crank 64 provided with an outstanding hand grip 65.
  • the upper end of the crank 64 is bored out to form a socket 66, in which is-located a coiled spring 67', and this coiled spring has its upper end connected to the inner Varm of a locking lever 68, fulcrumed as shown at 69 in a longitudinal slot 70 formed in the upper side of' the hand grip 65.
  • the outer arm 71 ofV said lever is normally located above the hand grip, and the innerarm is adapted to operate over a quadrant plate 72 iiXed to the adjacent side wall of the casing.
  • This quadrant plate is provided at its ends with stop shoulders 73, and is furthermore provided near one end with an upstanding lug 74 of less height than the shoulder, forming a socket 75 to receive the innerarm of the lever 71.
  • the aforesaid piston valve is -in its uppermost position, as illustrated in Figure 5, and assuming that air or other fluid under pressure is being delivered through the port 43 to the interior of the valve casing 39, the motive fluid supply port 43 and the outlet port 46 are in communication, so that motive fluid will enter the cylinder 34 above the piston 36 and operating on' the surface 36aL will move the piston downwardly, thereby elevating theV die 2O or in other words, opening ⁇ said dies for the reception of the steel.
  • the air below the pistony 36 can freely exhaust through the port 49.
  • valve Y is now in its lowermost position as indicated in Figure7. To return 'the parts to their initial position, it is only necessary to return the handle crank, whereupon the piston valve will be raised, first cutting'ollr1 the supply of motive fluid to the dolly hammer, then likewise closing the lower end of the cylinder to the motive fluid supply, and at the same time opening the lower exhaust port 42 to said supply, after which the exhaust from the upper end of the cylinder is closedV and motive fluid is'supplied against the upper surface 36a of the piston.
  • funnel 79 is employed that is bolted as'shown at 80 to the lower end of the platform 38 .directly beneath the openv lower end or exhaust port 42 of the valve casing 39.V This funnel yhas stood that various changes in the size, shape, y
  • the Vouter end of this valve is provided with a the combination with acasing, ⁇ of relatively movable. coacting' work-:clamping v".dies mounted' thereon, va, ⁇ cylinder within the casing,fa piston in the ycylinder forrelatively moving the dies, a valve .casing ⁇ .mounted ron the Acylinderwithin the casing and having a supply port', and outlet ports opening therefrom and into the cylinder oniopposite sides 0f the piston, afluid .operatedy hammer 'on the casing,'an outlet port from the valvegcasing 'in communication with the hammenavalve in the casing controlling the ports, and operating'means for the valve on the outside of the ycasing and having communication with said valve inside the casing.
  • the'combination'witha casing of relatively movable p mounted thereon, fa cylinder 'within the casing, la ypistony 1in' the cylinder for relatively moving the dies, an open ended valve casing mounted on the cylinder within the casing 'coacting' 'work-clamping Y ClQS ⁇ and having a supply port and outlet ports opening therefrom and into the cylinder on opposite sides of the piston, a fluid operated hammer on the casing, an outlet port from the valve casing in communication with the hammer, a reciprocatory piston valve in the casing controlling the communication between the supply port and the outlet port-s and between the outlet ports and the open ends'of the casing, and operating means for the valve on the outside of the casing and having connections with said valve inside the casing.
  • the combination with relatively movable coacting dies of fluid operated means for relatively moving the same toward and from each other, a valve casing having a supply port and outlet ports leading to the fluid operated means for alternately effecting their relative movement towards and from each other, a valve in the casing controlling communicationv between the ports, and means other than said valve for varying the amount of fluid permitted to pass ⁇ through the outlet portthrough which the motive fluid passes that controls the opening movement of the dies.
  • Ycasingor varyingV the amount of fluid that controls the opening ⁇ movement ofthe mov- Yable die, and an operatingA device for the latter valve located outside the outer casing'.
  • the combination Witha base or support, of a stationary and a coacting movable die mounted on the base or support, verticallymovable carrier rods supporting the movable die, a cross head connecting the carrier rods and having a depending stem located in a plane between the rods, a guideway on the base or support for the stein, and a motor located in the 'base or support at one side of the rods and cross head and having ⁇ means engaged With the cross head for moving the rods and the die supported thereby.

Description

F 1 1,617,225 eb 8 927 A. H. SKAER ET AL.
DRILL SHARPENER Filed Aug.11, 1925 e sheets-sheet s Feb 8 1927* A. H.'sKAER ET AL DRILL SHARPENER Filed Agg. 11, 3.923
num
j l ,6 sheertsu-Sheet 4 afferma Patented Feb. 8, 1927.
ARTHUR H. sRAER AND OMAR E. CLARK, oir-DENVER, COLORADO, AssIoNoRs YTo THE IDEXI'V'ERv ROCK DRILL MANUFACTRNG-` CGlVPANY,' OF
CORPORATION OF DELAVARE.
DENVER, COLORADO, A
DRILL sHARPENER;
Application mea August l11, 1923. seriaiivav` 656,985.
The present invention. relates to rock drill sharpeners of the type in which clamping dies are employed for holding a drill steel, and associated therewith is a Huid operated dollying hammer, the objeetbeing toA provide a compact and effective mechanism in which the operation of the different members is controlled in proper sequence by novel valve mechanism. v
In the accompanying drawings:
Figure 1 is aside elevationof a Sharpener equipped with the novel mechanism,
Figure2 is a front elevation of the, same with the front facing plate removed,
Figure 3 is a corresponding rear elevation,
Figure 4 is a vertical longitudinal :sectional View, -Y
v.Figures 5, 6 and 7 are verticalsectional views somewhat diagrammatic in their character, and illustrating the diiferent'positions of the controlling piston valve,
Figurev 8 is a Vvertical. sectional view Vthrough the valve casing` illustrating its mounting on the cylinder, 4
Figures 9 and l0 are horizontal sectional views on. the lines 9- 9 andzlO-l-l() ofFig- Y ure 8,
Figure 11 is a detail sectional view of vthe valve operating handle crank and lock,
Figure 12 is a detailview'of the quadrant rack or stop meansv for said handle crank. Y v n In the embodiment illustrated an outer casing 13` is employed, rhaving front [and rear openings 14- and 15 that'inay be closed by suitable detachable lplates or ywalls 16 and 17 shownin Figure 4. The top of the casing constitutes a platform or table 18,
on which are located coacting work holding dies 19 and 20 anda Huidt .operated dollying hammer 261. A
The die 19 is fixed onthe table top and the die; 2O moves down andp'up toward. and from the same. Itis 'carried byvertically reciprocating rods 22 spaced .apart and' connected at theirlower ends within the casing by a. cross head 23.y Thisy cross head has a central depending stem 24; slidably mountedA in a verticall bearing 25 formed in thelbase 26 of the casing. A lever 27fulcrumed'be.-
tween its endsVas illustratedat 28, `to and between depending'ears 29, yhas one end. connected to the cross headby a link 30, this linl;
.having apivotal connection 31 'with one end oit' the lever ,2T and .having itsfother end fitted ina lrecess 32 in the cross Ahead rand connected to said crosshead by apivot 33.
A Averticalcylinder 34 is mounted. in V,the rear portion of the casing, being suitably bolted to the base as =illustrated;at '35, v.and having a .reciprocatory Vpiston 3 6 therein. This pistonl hasa pitmanconnection 37 ,with
. the .rear .end of the lever :27. It vwill be evident `that when the piston 36 iselevated lit ywill cause a downward movement of the rods 22 anda corresponding movement ofthe die. 2O vtoward the diev 19. 011;,tlie other hand when the piston 36descendsthe die 2O will be elevate 1 1 l p I The cylinder 34'has a flattened portion 38 forming a base, to whichfis'bolted avertical tubular valve casing 39, fastening bolts being illustrated at 40. The valve casinglis open endend, and saidopen .endsdesignated 41 Vand 42respectively constitute exhaust ports. A .central supply port, .as shown at 43, opensinto Vthe central portion .of .the valve chamber and communicates -,with an internal vannular groove A44. A second internal annular Agroove `45 above the igroove 44, is in communicationwith a n`out let port 46 leading by la,y passageway '47',throughgthe wall oi' the cylindery 34y to a point rabove-the. piston 36, `'said I'piston .having ajrelatievely small annular pressure surface 36a. -Anf other internaly annular groove 48, located below theigroove44, has van outlet port 49 leading therefrom, and communicating bymeans of a passageway 50 with the interiorofthe cylinder 34 at its lower end below the piston 36. The lower surface Lof said piston 36b constitutes a pressure surface-.that comprises the entire-area of the piston. A fourth internal annular. groove 51 is .formed in the valve casing below Athe Agroove 48, land' an ou-tlet port 52, openingthererom, isconnected by a .hose 53 tothe vfluid operated hammer 21. It will, of course, be understood that this ciprocaltory -piston valve, comprising -a cenltral reduced bodyg54, having an upper head 55 anda lower `head156,-the heads fslidably fitting the interior of said casing. The valve is supported by a vertical stem 57 that projects upwardly within the casing and is preferably surrounded by a coiled spring 58 operating to normally hold the valve in its uppermost position, or as illus trated in Figure 5. rlhe stem is suitably connected to one arm 58 of a bell crank j ournaled within the casing, as shown at 59, and the other arm 60 of said bell crank has a link connection 61 with a crank arm 62 on a rock shaft 63 journaledin one side.v of the casing, and projectingtherefrom.- lThe projecting end'carries an upstanding handle crank 64 provided with an outstanding hand grip 65. As shown particularly in Figure 11, the upper end of the crank 64 is bored out to form a socket 66, in which is-located a coiled spring 67', and this coiled spring has its upper end connected to the inner Varm of a locking lever 68, fulcrumed as shown at 69 in a longitudinal slot 70 formed in the upper side of' the hand grip 65. The outer arm 71 ofV said lever is normally located above the hand grip, and the innerarm is adapted to operate over a quadrant plate 72 iiXed to the adjacent side wall of the casing. This quadrant plate is provided at its ends with stop shoulders 73, and is furthermore provided near one end with an upstanding lug 74 of less height than the shoulder, forming a socket 75 to receive the innerarm of the lever 71. With this oonstruction, it will be evident that the operator lever. VWvhen the crank is thus moved in one direction or the other, obviously the l piston valve 54-55-5'6 is reciprocated.
l/Vlien the aforesaid piston valve is -in its uppermost position, as illustrated in Figure 5, and assuming that air or other fluid under pressure is being delivered through the port 43 to the interior of the valve casing 39, the motive fluid supply port 43 and the outlet port 46 are in communication, so that motive fluid will enter the cylinder 34 above the piston 36 and operating on' the surface 36aL will move the piston downwardly, thereby elevating theV die 2O or in other words, opening` said dies for the reception of the steel. The air below the pistony 36 can freely exhaust through the port 49. and the lower 'A open end or exhaust port 42 of the valve casing, all of which are indicatedby the arrows in Figure.y When thesteel to be sharpened' has been placed between the dies 19 and 20, the opera-tor unlocks the handle crank 64 as above described, and swings said handle crank to the right, thereby moving the piston valve downwardly. VThe first action is to cause the head 55 of said piston valve tol pass across the .groove 45, thereby cutting off Ythe port 46 t from the fluid supply port 43. A continued movement causes the lower head 56 to pass below the groove 43, thereby bringing the supply port 43 and the outlet port 49 rinto communication, cutting off said port 49 'fronr vthe lower exhaust port 4Q. F luid under pressure! will now flow from the supply port 43 through the outlet port 49 and chamber 50 into the lower end of the cylinder 34 and acting against the relatively large area 36h of the-piston 36, will raise said piston with' very considerable force.` At the same time` the upper head will have passed below the port 46,v permitting the'fluid above the piston surface 36 to exhaust through the port 41. This is all indicated in `igure 6.
The upward movement of the piston 36 through the mechanism already described will cause the downward movement ot the die 2O toward the die 19, thereby clamping the steel'in place. As the piston valve continues its downward movement the lower head 56 will uncover the outlet port 52 and bring it into communication with the supply port 43 while the outlet port 49 continues in such communication. The motivefluid thus finds its way by means of said supply port 43 and hose y53 'to the dolly' hammer, thus initiating the operation of the latter 'after the steel has been clamped,1and in the well known manner the dolly acting on said steel will shape or sharpen the sam-e.
The valve Y is now in its lowermost position as indicated in Figure7. To return 'the parts to their initial position, it is only necessary to return the handle crank, whereupon the piston valve will be raised, first cutting'ollr1 the supply of motive fluid to the dolly hammer, then likewise closing the lower end of the cylinder to the motive fluid supply, and at the same time opening the lower exhaust port 42 to said supply, after which the exhaust from the upper end of the cylinder is closedV and motive fluid is'supplied against the upper surface 36a of the piston.
Inasmuch as these machines are employed Linder various air pressures, diliiculty has been experienced in controlling the speed ot the return or opening movement of the dies, as said opening' movement is obviously under no material resistance except the weight and inertia of the parts. Too rapid movement is therefore apt to result in strain and even damage. y In order to control this according to the pressure of the fluid used, the outlet port 46, vleading from the upper end of the valve casing 39, to the upper portion oi' the Vport to the second exhaust port.
what is in effect a needle valve 76, the inner end l77 of which is adapted lto enter more .or less into a portion of the port, andobviously control the amount of fiuid that will pass through said port in a given period.
handle 7 8 that is located outside of the cas ing as illustrated in Figure 4. i
In order to remove scale and dirt from l the dies, the exhaust from the lower end of the cylinder is utilized and funnel 79 is employed that is bolted as'shown at 80 to the lower end of the platform 38 .directly beneath the openv lower end or exhaust port 42 of the valve casing 39.V This funnel yhas stood that various changes in the size, shape, y
proportion and minor details of construction, may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.
Having thus fully described our invention, what we claim as new, and desire, to secure by Letters Patent, is
l. In apparatus of the character set forth,
the combination with coacting dies, lof a cylinder and a fluid operated piston in the cylinder for relatively moving the dies, a fluid operated hammer, a valve casing having a supply port, an outletport having a single line of connection with the hammer to supply motive fluid thereto for effecting its repeated operation, outlet ports communicating with the cylinder on opposite sides of the piston, and first and second exhaust port-s, and a piston valve'operating in the casing in one direction to-cause the supply portto be brought into communication with one of the outlet ports leading to the cylinder and simultaneously openingthe secondl of said outlet ports to one o f the exhaust ports, secondly affording communication between the supply port and the port leading to the hammer to supply fiuid thereto and cause its repeated operations while maintaining the first communication inthe cylinder and when said valve is moved in an opposite direction rst cutting off communication between the supply port and hammer, then cutting ofil communication between the supply-port and said iirst outlet port leading tothe cylinder, and thereafter openingl communication between the supply port and the other outlet portto the cylinder and opening the first mentioned outlet 2. In apparatus of the character described,
The Vouter end of this valve is provided with a the combination with acasing,` of relatively movable. coacting' work-:clamping v".dies mounted' thereon, va, `cylinder within the casing,fa piston in the ycylinder forrelatively moving the dies, a valve .casing `.mounted ron the Acylinderwithin the casing and having a supply port', and outlet ports opening therefrom and into the cylinder oniopposite sides 0f the piston, afluid .operatedy hammer 'on the casing,'an outlet port from the valvegcasing 'in communication with the hammenavalve in the casing controlling the ports, and operating'means for the valve on the outside of the ycasing and having communication with said valve inside the casing.
` 3.' In apparatus of the character"described, the'combination'witha casing, of relatively movable p mounted thereon, fa cylinder 'within the casing, la ypistony 1in' the cylinder for relatively moving the dies, an open ended valve casing mounted on the cylinder within the casing 'coacting' 'work-clamping Y ClQS` and having a supply port and outlet ports opening therefrom and into the cylinder on opposite sides of the piston,a fluid operated hammer on the casing, an outlet port from the valve casing in communication with the hammer, a reciprocatory piston valve in the casing controlling the communication between the supply port and the outlet port-s and between the outlet ports and the open ends'of the casing, and operating means for the valve on the outside of the casing and having connections with said valve inside the casing.
t. In apparatus of the character set forth,
the combination with relatively movable coacting dies, of fluid operated means for relatively moving the same toward and from each other, a valve casing having a supply port and outlet ports leading to the fluid operated means for alternately effecting their relative movement towards and from each other, a valve in the casing controlling communicationv between the ports, and means other than said valve for varying the amount of fluid permitted to pass` through the outlet portthrough which the motive fluid passes that controls the opening movement of the dies.
5. In apparatus of the character set forth, the combination with relatively movable coacting dies, of fluid operated means for relatively Vmoving the same, a valve casing havmounted on the casing, a cylinder in the l outside the outer casing, a valve in the outer.
Ycasingor varyingV the amount of fluid that controls the opening` movement ofthe mov- Yable die, and an operatingA device for the latter valve located outside the outer casing'.
7. In apparatus of the character set forth, the combination With a base orsupport, of a stationary and a eoacting movableV die mounted on the base or support, vertically movable carrier rods supporting the movable die, a cross head connecting` the carrier rods and having a'stem, a guideway for the stem,
and a motor for the movable die located at one sideV of the rods and cross head 'and having means engaged With the .cross head for moving the rods and the die supported thereby.
8. In apparatus of the character set forth, the combination Witha base or support, of a stationary and a coacting movable die mounted on the base or support, verticallymovable carrier rods supporting the movable die, a cross head connecting the carrier rods and having a depending stem located in a plane between the rods, a guideway on the base or support for the stein, and a motor located in the 'base or support at one side of the rods and cross head and having` means engaged With the cross head for moving the rods and the die supported thereby.
In testimony whereof, We aiix our signatures. Y
' ARTHUR H. SKAER.
OMAR'E. CLARK.
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